It was two years before the first Earth Day in 1970 when Garrett Hardin penned the famous essay “Tragedy of the Commons,” and it fit a certain bleak and despairing mood of the time. Paul Ehrlich had just published The Population Bomb, a Malthusian account of a world overwhelmed by sheer numbers of people. Against the backdrop of that gloom, Hardin’s theory came as another dose of bad news, “proving” that we also had no hope of controlling our appetite for natural resources. Since no one owned the oceans or the atmosphere, we would inevitably fish and pollute them into oblivion. Hardin offered a few suggestions, but his title summed it up: we were witnessing a tragedy whose script could not be revised.